A method for fabricating a nucleic acid nanostructure is disclosed, according to illustrative embodiments of a present invention. The method includes providing at least two single stranded nucleic acid sequences, forming elementary blocks. The method further includes synthesis of heterogeneous nucleic acid shapes by merging the blocks. The blocks are further mutated and consequently, the nucleic acid tetrominoes are formed. The tetrominoes are further assembled into supra molecular structures, thereby forming the nanostructures. The method provides fabrication using self-organized and heterogeneous nucleic acid structures. A system for fabricating nucleic acid nanostructures is also disclosed, according to another illustrative embodiment of the present invention.